Blasting cartridge



June 15, 1937. w H, wlNEMAN 2,083,584

BLAsTiNG CARTRIDGE Filed June 5, 1934 E Illlll 36 A J7 .i 63 .3.9 41 6a 67 @sw 6i 32 627;/

- Plame June 1s. i931 UNITED 'STATES PATENT OFFICE L m N l spasms. calumnias Wadellwlnemalnlii chigan by menne assignments, to Safety Mining pany, Chicago, lll., a corporation ot Illinois` Application June 5, 1934, Serial No. 729,110 zo claims. (ci. 1oz-s) Thisinvention relates to blasting cartridges, and more particularly to improvements in acartridge pf the type in which highly compressed gas is used as a blasting medium.

An object of this invention is to provide an improved blasting cartridge of the compressed gas type and having improved means for suddenly releasing the pressure when a predetermined blasting pressure is attained. Another object is to provide animproved blastingcartridge having improved valve mechanism and having associated therewith improved means for effecting quick opening of the valve mechanism to release suddenly the pressure when a predetermined blasting pressure is attained within the cartridge casing. These and other objects of the invention will, however, hereinafter more fully appear.

In the accompanying drawing there are shown for purposes of illustration several forms which the invention may assume in practice.

In this drawing,

Fig. 1 is a central, longitudinally extending, sectional view through the improved blasting cartridge construction in accordance with one illustrative form of the invention.

Fig. 2 is a view similar to Fig. 1 showing the parts in pressure releasing position.

Fig. 3 is a view similar'to Fig. l, showing a modified form of construction.

Fig. 4 is a fragmentary view similar to Fig. 2 showing the valve in pressure releasing position.

Fig. 5 isa cross sectional view taken on line 5-5 of Fig. 4.

Fig. 6 is` similar to Fig. 3 showing a still further i modiiied form of construction.

In the illustrative form of the invention shown in Figs. 1 and 2 there is shown a blasting cartridge of the type in which highly compressed gas is used as a blasting medium, and comprising a cylindrical metallic casing or shell I having a chamber 2 which is adapted to contain a charge of gas compressed to a high pressure. The outer end of this casing is closed by a head 3 threaded to the casing at 4 and locked in position by a Wire spring lock 5 of a known design, and comprising a Wire bent to a suitable form and having end portions projecting within notches cut in the adjacent ends of the casing and head. As illustrated, the head 3 is provided with a central bore 6 to which there" is conducted a highly compressed gas through a tube connection 1 threaded within the head wall 8. Threaded at 9 within the opposite or inner end of the casing I is a hollow cap II) perforated with discharge holes II extending from its central recess I2 to the exterior.. Connecting the pressure chamber 2 with the central recess oi' the cap I Il is an axial passage surrounded by a conical valve seat I3 with which engages the conical valve portion I4 of a pressure release valve I5. The wall of this valve seat I3 is annularly grooved at I6 to receive an annular ring "preferably composed of rubber and engageable with the valve portion I4 in the sealing of the valve on its seat. Threadedly connected at I 8 to the valve I 5 is an axial rod I 9 extending centrally through the chamber 2 and projecting within the chamber 6 within the rear head 3. Reciprocably mounted within the bore 6 is a piston 2li having an axial opening 2| through which the rod I9 extends and carrying a cup packing 22 for preventing leakage of compressed gas from the chamber 2 into the bore 6 past the piston and rod. This packing is held in position by a cap retaining plate 23 secured to the piston by screws 24, and inward movement of the piston 2li is limited by stop lugs 25 secured to the rod I9. Interposed between the piston and a collar 26 secured to the outer end of the rod and encircling the rod is a coil spring 21.

Highly compressed gas, herein compressed air under high pressure, is conducted through the tube 1 to the bore 6 in the head, through the bore and past the piston 20 exteriorly of the packing 22 to the pressure chamber 2. When a predetermined blasting pressure is attained within the chamber 2 the supply of compressed gas through the tube 1 is cut oil in any suitable manner and the bore Ii at the outer side of the piston connected to atmosphere through any suitable vent means under the control of the operator so that the pressure in the bore 6 is reduced thereby reducing the pressure acting on the rear area of the piston 20. 'I'he relatively high pressure within the chamber 2 acting on the inner pressure area of the piston causes the piston to move outwardly relative to the rod I9 while at the same time the spring is increasingly compressed. When the spring becomes compressed to a certain degree the same eiects sudden outward movment of the rod I 9 and the valve I 6 is quickly unseated thereby permitting a sudden release of the compressed gas from the chamber 2 through the chamber I2 and discharge holes I I in the cap I0 and as a result effecting breaking down of the material to be blasted.

In the modied form of construction shown in Figs. 3 to 5 inclusive, there is shown a cylindrical casing or shell 30 having a pressure receiving chamber 3l and communicating with this chamberis a bore 32 closed at the outer end of the cartridge by a head member 33. Threadedly connected at 34 to the inner end of the shell is a hollow cap 35 perforated with discharge holes 36 extending from its central recess 31 to the exterior. Connecting the inner end of the pressure chamber 3| with the recess 31 in the cap is an axial opening 38 surrounded by a conical valve seat 39 with which the conical valve portion 4|! of a pressure release valve 4I engages. As in the form of the invention shown in Figs. 1 and 2, this valve seat is annularly grooved at d2 to receive a rubber sealing ring 43. Reciprocable in the bore 32 is a piston 43 carrying a cup packing 45 for permitting ow of compressed gas from the bore 32 to the pressure chamber 3| but preventing leakage of pressure from the pressure chamber. Threadedly engaged with the piston M is a rod 436 herein formed integral with the valve 4|, and threadedly engaged with this rod is a nut 41 engaging a washer d8 for holding the cup packing i5 on the piston. In this instance formed in the piston is a valve chamber 69 having a valve seat 50 with which a ball valve 5| p chamber 3 l engages. This valve controls the communication of the valve chamber 49 with the bore 32 through passage 52. A passage 53 formed' in the rod 46 connects the valve chamber di) with the pressure Connected to the head 33 is a pipe connection 54 for supplying highly compressed gas through a passage 55 to the bore 32 at the outer side of the piston 4d, and for venting bore 32 when desired.

From the foregoing it will be evident that when compressed gas, herein air under high pressure, is supplied through the pipe connection 54 and passage 55 to the bore 32, the compressed gas will f iiow from the bore '32 through passage 52 past the pressure is attained within the pressure chamber 3i, the supply of compressed gas to the pipe connection 54 is cut oi and this pipe connection suitably connected to atmosphere. This will l cause the ball valve 5| to close the passage v52 and the relatively high pressure in the charnber 3| will move the piston M outwardly thereby to move the valve M into its unseated position shown in Fig. 4, and as a result the pressure in the chamber 3| is suddenly released through the axial recess 31 ln the cap and discharge holes 36.

In the modified form of construction shown in Fig. 6 the cartridge shell, pressure chamber, bore 32, outer head 33, the cap 35 and the valve 4| are similar to those disclosed in the form of invention shown in Figs. 2 to 5 inclusive. In this form of the invention, however, the piston structure for operating the valve 4| and the means for supplying compressed eas to the pressure chamber 3| are somewhat modified. In this instance, the rod 60, with which the valve 4| is integrally formed, has a shoulder 6| with which it engages an annular plate 62 forming the piston cal portion 68 adapted to iit in the axial bore 33 when the conical portion of the valve ls on the seat 39 thereby to provide a tighter seal between the pressure chamber and the cap discharge recess 31. Otherwise this form of the invention is similarto that shown in Figs. 3 to 5 inclusive.

When compressed gas is supplied through the pipe 54 and passage 55 to the bore 32 the compressed gas flows from the bore 32 past the cup packing 65 to the pressure chamber 3 I. When the desired blasting pressure is attained within the pressure chamber 3| the supply of compressed gas in the pipe connection 54 is cut off and the latter suitably vented to atmosphere. The sudden drop in pressure in the bore 32 causes the pressure in the chamber 3| to move the piston B2 rearwardly thereby to unseat the valve 3| and to release suddenly the blasting pressure from the chamber 3|.

As a result of this invention it will be noted that an improved blasting cartridge is provided of the type in which highly compressed gas is used as a blasting medium, having imp'roved and simplified means for suddenly releasing the blasting pressure from the pressure chamber when a predetermined pressure is attained within the cartridge casing. It will further be noted that an improved blasting cartridge is provided having improved pressure releasing valve mechanism and im proved and simplified means for supplying comi pressed gas to the pressure chamber and for actuating tlie valve mechanism to effect sudden release of the blasting pressure. These and other uses and advantages vof the improved blasting cartridge will be clearly apparent to those skilled in the art.

While I have in this application specifically described several forms which my invention may assume in practice, it will be understood that these forms of the same are shown for purposes of illustration, and that the invention mty be further modified and embodied in various other forms without departing `from its spirit or the scope of the appended claims.

What I claim as new and desire to secure by Letters Patent iszl. In a blasting cartridge, a casing having a chamber for receiving a blasting charge, a valve for releasing the pressure from said chamber, and

a piston actuated by the pressure in said chamber for actuating said valve, said piston having a packing serving as a check valve for the pressure supplied to said chamber.

2. In a blasting cartridge, a easing having a chamber for receiving a blasting charge, a valve for releasing the pressure from said chamber, a piston actuated by the pressure in said chamber for actuating said valve, and a compressible connection between said piston and said valve for permitting relative movement of said valve and piston.

3. In a blasting cartridge, a casing having a chamber for receiving a charge of blasting pressure, a valve for releasing said pressure from said chamber, and means controlled by the pressure in said chamber for actuating said valve comprising a rod, a piston and a yielding connection between said piston and rod.

4. In a blasting cartridge, a casing having a chamber for receiving a charge of blasting pressure, a valve for releasing the pressure from said chamber, a piston secured to the valve and controlled by the pressure in said chamber for moving said valve, and means carried by the periphery of said piston for controlling the flow of com- Cil . -chamben a pistonsecuredxto said valve and con-n trolled by the pressure in said chamber for actuating said valve, and combined valve and packing means carried by said piston in radially spaced relation to the axis thereof for controlling the supply of pressure i'iuid to said pressure c hamber. f

6. In a blasting cartridge, a casing having a chamber for receiving a charge of blasting pres sure, a. valve for releasing said pressure from said trolled by the pressure in said chamber for actuating said valve, and a cup packing carried by said piston for permitting pressure iluid to flow to said chamber but preventing leakage of pressure fluid from said chamber.

7. In a blasting cartridge, a casing having a chamber for receiving a charge of blasting pressure, a valve for releasing said pressure from said chamber, a piston secured to said valve and controlled by the pressure in said chamber for actuating said valve, a cup packing carried by said piston for permitting pressure fluid to flow to said chamber but preventing leakage of pressure fluid l from said chamber, and an expansible means carried by said piston for holding said cup packing in tight engagement with the wall of the bore within which said piston moves.

8. In a blasting cartridge a casing having a chamber for receiving a charge of blasting pressure, a valve controlled by the pressure in said chamber and movable inwardly for releasing the pressure from said chamber, a Valve seat facing inwardly toward said chamber and with which said valve engages, an annular groove formed in the walls of said seat, and a rubber ring mounted in said annulargroove and engaging said valve when the latter is in its closed position.

9. Ina blasting cartridge, a .casing having a chamber for receiving a charge of blasting pressure, a valve controlled by the pressure in said chamber and movable inwardly for releasing the pressure from said chamber, a valve seat facing inwardly toward said chamber and with which said valve engages, an annular groove formed in the Walls of said seat, a rubber ring mounted in said annular groove and engaging said valve when the latter is in its closed position, and a stop shoulder outwardly with respect to said chamber `beyond said ring, said valve having a shoulder engageable with said stop shoulder when said valve is closed.

10. In a blasting cartridge, a casing having a. chamber for receiving a charge of gas at a blasting pressure, a valve controlled by the pressure in said chamber and movable inwardly for controlling release of the gas, a valve seat facing inwardly toward said chamber and having a surl face whose trace on an axial plane makes an angle with the axis of the seat, said valve having a surface mating with said valve seat surface, spaced surfaces on the seat and valve respectively inclined relative to the rst mentioned surfaces, and a resilient packing ring carried by the seat and engaging the last mentioned surface on the valve.

11. In a blasting cartridge, a casing for receiving a charge of gas at a blasting pressure said casing having a discharge opening surrounded by a valve seat, a valve cooperating in the Isaid seat, and a piston controlling said valve and having a spring-pressed, combined packing and check valve at its outer edge.

12. In a blasting cartridge, a, casing having a chamber for receiving a blasting charge, a valve for releasing the charge from said chamber therein, a piston actuated by the pressure in said chamber for actuating said valve, a connection between said piston and said valve for permitting relative movement of said valve and piston, and stop means for limiting relative movement between said valve and piston.

13. In a blasting cartridge, a casing having a chamber for receiving a charge of blasting pressure, a valve for releasing said pressure fljpmV "said'chamber, and means controlled by the pressure in said chamber for actuating said valve comprising a rod secured to said valve, a piston, and a yielding connection between said piston and rod, and sealing means associated with said yielding connection for preventing leakage of pressure from said chamber past said rod.

14. In a blasting cartridge, a casing having a chamber for receiving a charge of blasting pressure, a valve for releasing said pressure from said chamber, and means controlled by the pressure in said chamber for actuating said valve comprising a rod secured to said valve, and a piston for actuating said rod, said rod and piston being relatively movable, and a seal carried by said piston for sealingly engaging the rod periphery for preventing leakage from said chamber past said rod.

15. In a blasting cartridge, a casing having a chamber for receiving a charge of blasting pressure, a valve for releasing said pressure from said chamber, and means controlled by the pressure in said chamber for actuating said valve comprising a rod secured to said valve and having an abutment at its outer end, a piston for actuating said rod and having a packed opening through which said rod extends, and a spring interposed between said rod abutment and said piston.

16. In a blasting cartridge, a casing having a chamber for receiving a blasting charge, a valve for releasing the pressure from said chamber, and means for effecting sudden actuation of said valve, said means including an element movable relative to the valve by the pressure in said chamber and a compressible spring interposed in the connection between the element and the valve for transmitting the pressure of the charge from the element to the valve.

17. In a blasting cartridge, a casing having a chamber for receiving a blasting charge, a valve for releasing the pressure from said chamber, and means for eiecting sudden actuation of said valve, said means including a resilient member operatively connected to said valve and adapted to be distorted to store valve actuating energy, and a device actuated by the pressure in said chamber for distorting said member.

18. In a blasting cartridge, a casing having a chamber for receiving a blasting charge, a valve for releasing the pressure from said chamber, a rod connected to said valve, a piston loose on said rod, means connecting the pistonto said rod, and common means for packing both the piston and the rod and the piston and the surrounding casing wall.

19. In a blasting cartridge, a casing having a chamber for receiving a blasting charge, a valve for releasing the pressure from said chamber,

rod operatively connected to said valve, a valve actuating piston movably mounted on said rod and single means for packing between the rod, the piston and the surrounding casing wall and for serving as a check valve for the pressure supplied to said chamber.

WADE H. WINEMAN. 

